1. Field of the Invention
The present invention relates to a controllable one-way clutch for a vehicle and more particularly, to an improved controllable one-way clutch for a vehicle, which functions as a one-way clutch and does not transfer the driving force in any direction when the hydraulic pressure terminates.
2. Description of Related Art
Generally, one-way clutches inserted between a driven race and a driving race for transferring the driving force in a one-way direction are well known in the art. An example of the known art is utilized in an automatic transmission.
Such a conventional clutch comprises an inner race 107 and an outer race 101 as shown in FIG. 4. A groove 103 is formed in the inner side of the outer race 101, the groove 103 having a narrow opening with sidewalls 106 and a facing wall 102. The groove 103 includes a spring 104 and a roller 105 connected to the spring 104.
When the inner race 107 rotates in the clockwise direction, the roller 105 rolls in the groove 103 with the roller 105 inserted between the facing wall 102 and the inner race 107. Therefore, because of a wedge function, the driving force can be transferred from the inner race 107 to the outer race 101.
On the contrary, when the inner race 107 rotates in the counter-clockwise direction, the roller 105 is released from the wedge operation. Therefore, the driving force cannot transfer from the inner race 107 to the outer race 101.
As shown in FIG. 13, a conventional multiplate clutch is provided for use in an automatic transmission of a motorcycle and an automobile. The conventional multiple clutch comprises a plurality of clutch plates 117 vertically disposed in an uneven inner wheel 115 of a clutch retainer 114, and a plurality of clutch discs 112 vertically disposed in an uneven outer wheel 111 of a hub 116 such that the clutch discs 112 are disposed within the clutch plates 117.
When hydraulic pressure is supplied to a cylinder 108, a piston 113 in the clutch retainer 114 pushes against the clutch plates 117 so that the clutch discs 112 are compressed and the driving force transfers. Also, the clutch plates 117 cannot be separated from the clutch retainer 114 and a friction material 110 attaches to both sides of the clutch discs 112.
However, such conventional one-way clutches suffer from a number of problems, such as for example, it is very difficult to allow a loose rotation in both directions, it is expensive to manufacture since it requires a number of parts such as a plurality of clutch plates and clutch discs, and it is complicated in structure.